A similar drive mechanism is known in this technical field from the patent DE-OS 26 30 512, for example. The drive mechanism shown there functions as an electromagnetic valve drive mechanism for the gas exchange valves of an internal combustion engine. For drive mechanisms of this type, the customarily-used traditional cam drive mechanism, which has a camshaft and radial cams and is connected via a drive mechanism to the crankshaft, can be omitted. Generally, a system of this sort functions as a spring mass oscillator with its own resonance frequency. The lifting magnets, which are arranged at a distance from the excursion limits of the valve, cause an opening and closing of the valve by the switching on and off of electric power. It is disadvantageous in the system previously described that an extreme development of noise occurs due to the unavoidable mechanical stop in the region of the excursion limits. In addition, a variation of the valve lift itself is not possible, so that it is not possible to make smaller gas exchange cross sections than the maximum cross section at the valve. These smaller gas exchange cross sections, however, prove to be sensible in multi-valve technology, for example, such as four-valve technology, while the internal combustion engine is running at idle or under partial load. In this case, a higher angular momentum and thus an improved mixture formation and combustion is expected due to the reduced gas exchange cross section at the valve.
In addition, there is no suggestion to the specialist from the cited state of the art of how he can recover at least a portion of the electric power conducted into the system. Anyway, it can be determined in and of itself that the system previously known from the patent DE-OS 26 30 512 consumes a relatively large amount of power (approx. 3 kW) and is difficult to control due to its mechanics alone. Furthermore, because of its mean position sensitivity, the costly installation of a hydraulic play compensation component is recommended.
Furthermore, in the extreme case, not only can undesired noises be emitted by the hard end stops, but also the valve can expand in an undesirable way due to its jerky change in acceleration, or in the extreme case, its plate can even tear off.
Professionals have attempted, of course, to eliminate the disadvantage of the hard touch-down of the valve, for example, by hydraulic damping measures which are known to those skilled in the art and not explained in greater detail here. However, these measures have proven to be very costly and difficult to control in construction.